Strap guide



May 23, 1961 A. L. WlNKLER STRAP GUIDE Filed May 9, 1960 19 \V'INVENTOR.

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mun... 99mm;

STRAP GUIDE Alvin L. Winkler, Chicago, 111., assignor to Acme SteelCompany, Chicago, Ill., a corporation of Illinois Filed May 9, 1960,Ser. No. 27,556

1'2v Claims. (Cl. 100--25) This invention relates to the art of strapguide tracks and particularly to one which enhances the use of aconventional type track wherein a length of strapping is guided aroundan object to be strapped prior to tensioning of the strap on the objectand connecting together the ends of the strap length.

When strapping objects at the present time, it is common to secure theobject or load by means of the straps to an underlying support palletwhich provides a convenient means on which the object can be supportedduring subsequent handling, storage and shipment. On certain typepallets where the pallet consists of a platform supported by post typelegs or longitudinal runners, little difficulty is encountered inproperly encircling the straps around the pallet to secure it to theload or object which it supports. However, when a double faced pallet isused, viz., one which consists of two parallel faces or sheets spacedapart by means of spacers or legs, it is desirable that the strapsextend in the space between the two faces of the pallet so that theupper face only is actually strapped to the object. The obvious way ofthreading the straps through this space is manually by passing theleading strap end from one side of the pallet to the other. This is atime consuming operation and does not lend itself to high enoughproduction to keep abreast of the swiftness of the ordinary high speedassembly line.

it is, therefore, the principal object of this invention to provide animproved strap guide track having novel retractable means which can beextended into the space between the two faces of a double faced palletwhere the means provides a guide for facilitating the passage of a straplength endwise through the space so that a strap can be quickly andeasily encircled around an object supported on the pallet.

In order to accomplish this object, it is another object to provide anovel type retractable guide which can be first inserted into the spaceof the pallet when the strap is to be encircled on the object, and thenretracted after encircling of the strap has been completed.

The form of the retractable means of this invention is a metal slatwhich is bowed into a transverse concavoconvex cross section to firstprovide rigidity for proper support of a strap and secondly provide atrough into which the strap can be properly guided. Also, for spaceconservation, the metal slat is suspended vertically in its initialposition and is of such a nature that it is guided in its travel arounda right angle bend which causes it to change from a vertical directionto a horizontal direction in order to properly be guided into the spacebetween the pallet faces during the strap encircling operation.

It is another object to provide a retractable guide as described whichis powered by reversible means so that it can be either extended orretracted as required.

Other objects and advantages of the invention should become apparentupon reference to the accompanying drawings, in which nite States PatentFig. 1 shows a partially cutaway and partial sectional side elevation ofstrapping apparatus embodying the invention.

Fig. 2 shows a section of the apparatus of Fig. las viewed along theline 22 of Fig. 1.

Fig. 3 shows a sectional view along the line 3-3 of Fig. 2 andparticularly shows the concavo-convex shape of the guide beams 'as wellas its marginal guides.

Fig. 4 shows a sectional view approximately along the line 44 of Fig. land particularly shows the retractable guide and its roller guides inthe region where the retractable guide is bent at a corner for thepurpose of changing its direction of travel.

Fig. 5 shows a sectional view along the line 5-5 of Fig. 1 andparticularly shows the retractable guide sup port means and how it isguided vertically relative to the frame of the apparatus, and

Fig. 6 shows a sectional view along the line 66 of Fig. l andparticularly shows the cross sectional shape of the form of strap guidetube used with the invention.

The particular embodiment of the invention as shown is mounted on aframe 1 which ordinarily rests on the floor where the invention is to beused. The frame 1 is provided with a conveyor 2 consisting of aplurality of spaced parallel positioned rollers 3 journaled to theframe 1. These rollers 3 are freely journaled so that an object can berolled across their upper surfaces with a minimum of efifort. Secured tothe rear of the rollers in a vertical direction from the frame 1 is anupright member 4 whose upper end is provided with a horizontal arm 5extending in cantilever from it and directly over the region of theconveyor rollers 3. Secured by means of L-shaped clips 6 on either sideof the upright member 4 and the horizontal member 5 is a flexible strapguide tube 7. The

- clips are held in place on the members 4 and 5 by means of screws 8 asbest shown in Fig. 6. The guide tube 7 terminates at its upper end 9slightly beyond the end of the horizontal member 5 while its lower end10 terminates approximately slightly above the level of the rollers 3and in the vicinity of their rear ends.

The guide tube 7 is preferably manufactured from flexible plastic orrubber and can be extruded into the cross sectional shape shown in Fig.6. Although this plastic tube type guide is shown, there are many otherways of manufacturing guide tubes to perform the same general functionand the particular structure shown forms no part of the invention perse, as hereinafter claimed.

Since plastic or rubber ordinarily is soft enough that it can create asnag problem with the leading end of a strap fed through a guide tubemade from it, a backing strip 11 of stainless steel or other smoothmetal is positioned through the tube for its entire length. Its ends 11aand 11b are curled around the ends 9 and 10 of the tube in order toretain it positioned in the tube.

Extending parallel to the horizontal arm 5 is another arm 12 which isalso supported in cantilever from thev upright member 4. It is suppliedwith a motor 13 having a feed wheel 14 mounted on its shaft. Directlybelow the feed wheel 14 is an idler wheel 15 mounted on another shaft.The idler wheel 15 is positioned closely enough to the feed wheel 14 sothat when strap 16 is positioned between the two wheels 14 and 15 andthe feed wheel 14 is rotated, the strap 16 is caused to movelongitudinally between the wheels in a direction dependent upon thedirection of rotation of the feed wheel 14. The idler wheel 15 isnecessarily free wheeling in either direction. For convenience, theidler wheel 15 can be made retractable away from the feed wheel 14 topermit easy removal of the strap 16 when necessary but this forms nopart of the invention. The guide tube 7 is provided with an enlargedvase 7;:

2,985,098 Patented May 23, 1961 which is the portion held bythe clips 6.Attached to the base portion 7a are two flexible arms 7b and 7c which intheir normal positions abut at their ends along a line of contact 7d. Inthese positions, the arms 7b and 7.c form a circle having a longitudinal.circular opening .7e extending entirely through the guide tube ,7 fromone end to the other. When the guide tube is used for guiding straparound an object, the strap 16 is passed entirely through the guide tube7. When it is necessary to remove the strap from the guide tube 7 thestrap is pulled away from the guide tube and the pulling force causesthe strap 16 to cam against the arms 7b and 7c and spread them apart tothe positions as indicated in phantom lines in Fig. 6 where an openinglarge enough for the strap 16 to be removed is created. After the strapis removed, the natural resiliency of the arms 7b and 70 causes them toreturn to their initial positions. Since the arms 7b and 7c are flexiblefor their entire length, the strap 16 can be stripped from the tube 7progressively from end to end.

Also secured to the frame 1 is a T-shaped vertical track 17 whose lowerend is secured to a projection 18 of the housing which contains a gearreducer 19. Secured to the lower end of the gear reducer 19 is a motor20 which is used to drive the gear reducer mechanism. The gear reduceris provided with a shaft 21 which has an outer end secured to a chainsprocket 22 which is rotated with the shaft 21 as the motor is actuated.At the upper end of the T-shaped track 17 is a bracket 23 which isprovided with a threaded shaft 24 on which is rotatably mounted anotherchain sprocket 25.

Encircled about both of the chain sprockets 22 and 25 is a length ofchain 26 whose two ends 27 and 28 are secured to a bracket 29 so thatthe chain including the bracket 29 forms a closed loop encircled aboutthe sprockets 22 and 25. As shown in Fig. 5, the bracket 29 is shapedwith two inwardly extending tongues 30 and 31 which engage the frontface of the back wall of the T-shaped track 17. Two rollers 32 and 33are journaled in the walls of the bracket 29 and are positioned toengage the rear surface of the back wall of the T-shaped track 17. Inthis manher the bracket is positioned in a fixed transverse position bythe tongues 30 and 31 and the rollers 32 and 33, but the fit of thebracket 29 is loose enough on the track 17 that it may be movedlongitudinally relative to it. At the side of the bracket 29 isconnected by means of screws 34 a T-shaped bracket 35 which has securedto its free end by means of screws 36 the upper end 37 of theretractable strap guide 38. This upper end 37 is flattened to conform tothe flat shape of the bracket 35 but, immediately below the bracket, theguide is provided with a concavo-convex shape in cross section. Thisstrap guide 38 extends vertically downwardly past two flanged guiderolls 39 and 40 which guide the rear surface of the guide as viewed inFig. 3. These guide rolls 39 and 40 are journaled in brackets 41 securedto the T-shaped track 17. After passing by the guide rolls 39 and 40 thestrap guide 38 extends around two other guide rolls 42 and 43 whichguide the strap guide 38 through a bend to change the direction of thestrap guide from the vertical to the horizontal. The relative shapes andpositions of these guide rolls 42 and 43 are best shown in Fig. 4. Afteremerging from the region of the guide rolls 42 and 43, the guide track38 is guided at its lower surface by means of two more guide rolls 4'4and 45 which are identical to the guide rolls 39 and 40. These guiderolls 44 and 45 are journaled in suitable brackets to the frame 1.

In operation, when it is desired to strap an object or load onto adouble faced pallet 46, the motor 20 is energized in a direction whichcauses the chain sprocket 22 to be rotated in a direction to lower thebracket 29 in a direction indicated by the arrow 47 in Fig. 1. Thiscauses the retractable strap guide 38 to be lowered vertically and thisin turn causes its forward end 38a to be extended horizontally. With thepallet 46 properly positioned on the conveyor rollers 3 with its load46a resting upon it, the leading end 38a of the strap guide extends intothe space 48 between the two parallel faces 46b and 460 of the pallet46. With the legs or spacers 46d positioned at the four corners of thepallet, they provide no interference for obstructing movement of thestrap guide 38; After the leading end 38a of the strap guide is passedentirely through the opening 48 of the pallet, the motor 20 isde-energized to arrest the movement of the strap guide 38. Then, alength of strap is fed in the direction of the arrow 49 between the feedrolls 14 and 15, into the end 9 of the strap guide tube 7, entirelythrough it, and out through the exit end 10 where it contacts the uppersurface of the strap guide 38 which guides it from the rear side of thepallet through the space 48 of the pallet and out the front side of thepallet. The leading strap end 16a then projects approximately as shownin Fig. 1 in a position parallel to the supply end 16b of the strap. 3

With the strap ends and 16b so positioned, they are moved relative toeach other in such a way that the strap loop formed by the strap 16 iswithdrawn from the strap guide tube 7 in a manner as previouslydescribed. Upon withdrawal of the strap 16, it is tensioned byconventional hand or powered tools and the two overlapping strap ends16a and 1612 are then secured together to provide an encircling tautbinder loop of strap securing the load 46a to the pallet 46.

After this has been accomplished, the motor 20 is energized to rotate inan opposite direction and cause the bracket 29 to be elevated verticallyto cause the leading end 3841' of the guide track 38 to be rotated clearof the opening 48 in the pallet 46. The strapped pallet is then readyfor removal to another station where it is ordinarily stored or madeready for shipment. Although no stop mechanism is shown to limit thetravel of the bracket 29 with consequent travel limitations of the strapguide track 38, stops can be provided. Also, even though only one formof strap guide tube 7 has been shown, the strap guide track 38 can beused with other types of strap guide tubes or even without any and stillperform in an eflicient manner.

It is apparent that the strap guide 38 flattens from its ordinaryconcavo-convex shape to a flatter shape as indicated in Fig. 4 as itbends around the guide rollers 42 and 43. Also, it is apparent that thestrap guide 33 returns to its original concavo-convex shape along itsstraight portions after the strap guide passes around the bend. Thismeans that the strip material from which the strap guide is made must beresilient as well as flexible. It has been found that a spring tempersteel of fifteenthousandths thickness works very well for this purposewhere the width of the strap guide is approximately four inches and thedepth of the arc of the concaveconvex shape is approximately one inch.The steel is preferably of a stainless type in order to eliminate therusting problem without requiring plating, which is not too practical ona metal strip subject to the flexure of this particular strap guide. Theparticular transverse shape of this particular strap guide is alsosuflicient to impart enough rigidity to the strap guide that it isselfsupporting in cantilever as required when it is inserted through theopening 48 of a pallet 46.

Although only a single embodiment of the invention has been shown anddescribed, it should be understood that the invention can be made inmany different ways without departing from the true scope of theinvention as defined by the appended claims.

I claim:

1. The combination in strapping apparatus, of sup port means forsupporting a pallet of a type having a horizontal opening extendingthrough it, a retractable sheet metal strap guide, and means forextending the retractable strap guide through the horizontal opening ofthe pallet where it can guide a strap fed endwise through the opening,said strap guide being of conoavoconvex cross-section to impart rigidityto it so that it is self-supporting in cantilever.

2. The combination in strapping apparatus, of support means forsupporting a pallet of a type having a horizontal opening extendingthrough it, a retractable sheet metal strap guide, and means forextending said guide through the horizontal opening of the pallet Whereit can guide a strap fed endwise through the opening, said strap guidebeing of concavo convex cross-section to impart rigidity to it so thatit is self-supporting in cantilever and its concave side facing upwardas a trough for guiding and supporting said strap.

3. The combination in strapping apparatus, of support means forsupporting a pallet of a type having a horizontal opening extendingthrough it, a retractable sheet metal strap guide, means for bothretracting and extending the retractable strap guide through thehorizontal opening of the pallet, the guide being of coneavoconvexcross-section to impart rigidity to it and its concave side facingupward as a trough for guiding a strap fed endwise over it when theguide is in its extended position, the sheet metal from which the strapguide is made being flexible enough to allow the guide to be bent tofollow a non-rectilinear path as the guide is extended and retracted,the sheet metal of the guide also being resilient enough to cause theguide to retain its concave-convex cross-section along its straight pathportions.

4. The combination in strapping apparatus, of support means forsupporting a pallet of a type having a horizontal opening extendingthrough it, a retractable sheet metal strap guide, drive means for bothretracting and extending the retractable strap guide through thehorizontal opening of the pallet, the guide being of concave-convexcross-section to impart rigidity to it and its concave side facingupward as a trough for guiding a strap fed endwise over it when theguide is in its extended position, the sheet metal from which the strapguide is made being flexible enough to allow the guide to be bent into anon-rectilinear path as the guide is extended and retracted, the sheetmetal of the guide also being resilient enough to cause the guide toretain its eoncavo-convex cross-section during its straight pathportions, said drive means having a sprocket driven chain secured to oneend of said strap guide.

5. The combination in strapping apparatus, of horizontal support meansfor supporting a pallet of a type having a horizontal opening extendingthrough it, a retractable sheet metal strap guide, drive means for bothretracting and extending the retractable strap guide through thehorizontal opening of the pallet, said strap guide being flexible sothat it can be bent longitudinally into a non-rectilinear shape, guidemeans for guiding the strap guide through an L-shaped path with itsleading end extending horizontally and its rear end extendingvertically, said drive means being connected to said rear end, actuationof the drive means in one direction causing said rear end to be loweredand said leading end to be extended into the region of the opening inthe pallet, and actuation of the drive means in the opposite directioncausing said rear end to be elevated and said leading end to beretracted from the region of the opening in the pallet.

6. The combination of claim 5 characterized by, said strap guide beingof concavo-convex cross-section to impart rigidity to it suflicient tomake its leading end selfsupporting when it is positioned through theopening in the pallet.

7. The combination of claim 5 characterized by, said strap guide beingof 'concavo-convex cross-section to impart rigidity to it sufficient tomake its leading end selfsupporting when it is positioned through theopening in the pallet, said strap guide also being resilient enough toallow it to flatten in cross-section where bent and to return to itsconcavo-convex cross-section along its straight path portions.

8. The combination of claim 5 characterized by, said strap guide beingof concave-convex cross-section to impart rigidity to it suflicient tomake its leading end selfsupport-ing when it is positioned through theopening in the pallet, the concave side of the leading end facing upwardas a trough for supporting and guiding a strap fed over it. I

9. The combination in strapping apparatus, of support means forsupporting a pallet of a type having a horizontal opening extendingthrough it, a retractable strap guide, and means for extending theretractable strap guide through the horizontal opening of the palletwhere it can guide a strap fed endwise through the opening, said strapguide being of concavo-co-nvex cross-section to impart rigidity to it sothat it is self-supporting in cantilever.

10. The combination in strapping apparatus, of support means forsupporting a pallet of a type having a horizontal opening extendingthrough it, a retractable strap guide, and means for extending saidguide through the horizontal opening of the pallet where it can guide astrap fed endwise through the opening, said strap guide being ofconcave-convex cross-section to impart rigidity to it so that it isself-supporting in cantilever and its concave side facing upward as atrough for guiding and supporting said strap.

11. The combination in strapping apparatus, of support means forsupporting a pallet of a type having a horizontal opening extendingthrough it, a retractable strap guide, means for both retracting andextending the retractable strap guide through the horizontal opening ofthe pallet, the guide being of concave-convex crosssection to impartrigidity to it and its concave side facing upward as a trough forguiding a strap fed endwise over it when the guide is in its extendedposition, the material from which the strap guide is made being flexibleenough to allow the guide to be bent to follow a non-rectilinear path asthe guide is extended and retracted, the material of the guide alsobeing resilient enough to cause the guide to retain its concave-convexcross-section along its straight path portions.

12. The combination in strapping apparatus, or horizontal support meansfor supporting a pallet of a type having a horizontal opening extendingthrough it, a retractable strap guide, drive means for both retractingand extending the retractable strap guide through the horizontal openingof the pallet, said strap guide being flexible so that it can be bentlongitudinally into a nonrectilinear shape, guide means for guiding thestrap guide through an L-shaped path with its leading end extendinghorizontally and its rear end extending vertically, said drive meansbeing connected to said rear end, actuation of the drive means in onedirection causing said rear end to be lowered and said leading end to beextended into the region of the opening in the pallet, and actuation ofthe drive means in the opposite direction causing said rear end to beelevated and said leading end to be retracted from the region of theopening in the pallet.

No references cited.

